单作紫花苜蓿田夏季套作不同饲草作物生产性能、效益评价

为解决海河平原区苜蓿第3~5茬草雨季收获难的问题。于2011-2016年在位于河北衡水的河北省农林科学院旱作所试验站开展了单作紫花苜蓿田夏季套作5种不同饲草作物模式评价研究,以及单作紫花苜蓿田夏季套作青贮玉米的生产性能比较研究。结果表明,单作紫花苜蓿田夏季套作不同饲草作物模式评价研究得出,30-30 cm、20-40 cm两种行距处理下的单作苜蓿小区干草产量无显著差异(P>0.05);套作高丹草处理下苜蓿第2年前2茬干草产量显著低于单作苜蓿小区干草产量(P<0.05);套作青贮玉米处理后的总食物当量数显著高于单作苜蓿小区(P<0.05),但套作青贮玉米处理后的总经济效益与单作苜蓿小区无显著差异(P>0.05);套作青贮玉米处理下的平均光能利用率、水分利用效率、土地当量比均显著高于单作苜蓿小区(P<0.05)。单作紫花苜蓿田夏季套作青贮玉米的生产性能比较研究得出,30-30 cm、20-40 cm行距套作青贮玉米处理下的苜蓿前2茬干草产量、总食物当量数、总经济效益、平均光能利用率、水分利用效率、土地当量比均无显著差异(P>0.05)。综合得出,海河平原区单作紫花苜蓿田夏季套作青贮玉米的关键种植技术为:单作苜蓿田采用20-40 cm宽窄行秋播种植,于第2年前2茬苜蓿草收获后,在宽行中间套作青贮玉米,青贮玉米密度在6 万株·hm^-2以内,9月底将套作的青贮玉米与苜蓿一起收获,之后苜蓿田苜蓿正常越冬,下一年再重复种植青贮玉米。该模式在保证与单作苜蓿同等经济效益的前提下,可有效解决苜蓿3~5茬草雨季收获难、资源利用效率低的问题。

Evaluation on production performance and economic benefit of the single alfalfa filed interplanting different forage crops in summer

On the Haihe plain, the traditional 3-5 cutting of alfalfa are difficult to achieve in wet growing seasons. To explore this problem, two field experiments were conducted from 2011 to 2016 to analyze the production performance and economic benefit of interplanting alfalfa with various forage crops in summer. Five different forage crops were evaluated: silage maize, Sorghum bicolor×Sorghum sudanense, Dolichos lablab, fodder soybean, and forage millet. The results indicated that there were no significant differences between 30-30 cm and 20-40 cm row spacing treatments (P>0.05). The hay yield of the first two cuts of alfalfa for the second year when alfalfa was interplanted with S. bicolor×S. sudanense was significantly lower than for alfalfa alone (P<0.05). The total feed equivalent units when interplanting silage maize with alfalfa were significantly higher than for alfalfa alone (P<0.05); but the total economic benefits were not significantly different (P>0.05). The average solar energy use efficiency, water use efficiency, and land equivalent ratio when interplanting silage maize and alfalfa in summer were significantly higher than for alfalfa alone (P<0.05. Other research into the yield performance for alfalfa interplanted with silage corn showed that there were no significant differences (P>0.05) in the first two cuts between 30-30 cm and 20-40 cm row spacing treatments for hay yield, total feed equivalent units, total economic benefit, average solar energy use efficiency, water use efficiency, land equivalent ratio. Considering all the results, the optimal planting details for alfalfa interplanted with silage maize are as follows: the alfalfa field is planted in autumn using alternate wide and narrow row spaces of 20 and 40 cm. The silage corn is interplanted in the wide row space after the second cut of alfalfa is harvested in second year. The plant density of silage maize was less than 60000 plants·ha^-1 and the maize is harvested with alfalfa at the end of September, after which the alfalfa overwinters normally. The following year silage maize is replanted as the above. The interplanting methodology developed in this study is more easily implemented than the traditional 3-5 cuts of alfalfa in wet growing seasons and enhances solar, water and land resource use efficiency with the promise of corresponding economic benefits.